Automated content source validation for streaming data

ABSTRACT

One or more validation keys are embedded in a data stream at a server. A client requests the data stream from the server. The server sends the data stream to the client. The client receives the data stream, and samples the data stream to detect one or more validation keys.

RELATED APPLICATION

This application is a Continuation Application of U.S. application Ser.No. 10/016,740, entitled AUTOMATED CONTENT SOURCE VALIDATION FORSTREAMING DATA, filed on Oct. 30, 2001, and priority is claimed thereof.

FIELD OF THE INVENTION

The present invention relates to the field of electronic contentdistribution. More particularly, the present invention relates to thefield of streaming media content distribution.

BACKGROUND

Streaming is a technique for transferring data such that it can beprocessed as a steady and continuous stream. Many real-time events, suchas live news items, have to be streaming events or else they may becomemuch less relevant and less valuable. Also, streaming allows a personalcomputer (PC) user connected to the Internet to play a multimedia file,such as an audio or video file, in real time without having to wait forthe entire file to be downloaded. This is important because many usersdo not have fast enough access to the Internet to download a largemultimedia file in an adequately short amount of time. Typically, datastreams are generated and distributed by streaming content providers(SCPs).

An SCP may map a data stream to a Uniform Resource Locator (URL) toprovide users access to the data stream through readily available playerprograms, which are commonly integrated with Internet browser programs.To begin a viewing or listening session, a user may direct a playerprogram or browser program to the URL of a desired data stream. However,if the URL mapping of the desired data stream is incorrect, the user mayreceive an unexpected data stream. As an example, a user expectingclassical music may receive hard rock music. Incorrect URL mappings maybe introduced through various elements in distribution logic used todeliver the data stream from its source to the end user.

An SCP may provide streaming content generation and delivery services toresellers of streaming content, such as Internet radio stations andInternet service providers (ISPs), who provide end users access to thestreaming content. It is common for a service level agreement (SLA)between an SCP and a reseller to include a provision that commits theSCP to a specified level of content delivery accuracy, as well aspenalty provisions if the specified level of accuracy is not achieved.

In today's Internet content delivery systems, there are no mechanisms tobind a URL and the content it represents, ensuring that the intendedcontent gets delivered to users. Therefore, in an attempt to assureaccuracy, an SCP may employ human operators to direct a player programto the URL of a data stream in order to validate the content is streamedfrom the expected source. To employ human operators for content sourcevalidation (CSV) is expensive and directly impacts scalability ofoperations due to the limited number of data streams a human operatorcan validate. Further, because the process involves human interaction,the possibility of human error exists.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation in the figures of the accompanying drawings, in which likereferences indicate similar elements, and in which:

FIG. 1 shows a global view of an exemplary streaming content deliverynetwork (SCDN) capable of performing automated content source validation(CSV).

FIG. 2 shows a server-client view of an exemplary SCDN capable ofperforming automated CSV.

FIG. 3 shows a flow diagram describing the operation of content sourcevalidation according to one embodiment of the present invention.

FIG. 4 shows an exemplary data packet with a location and a length of anembedded key identified in a packet header.

FIG. 5 shows an exemplary database to store validation keys withassociated uniform resource locators (URLs).

DETAILED DESCRIPTION

The following detailed description sets forth an embodiment orembodiments in accordance with the present invention. In the followingdescription, numerous details are set forth. It will be apparent,however, to one skilled in the art, that the present invention may bepracticed without these specific details. In other instances, well-knownstructures and devices are shown in block diagram form, rather than indetail, in order to avoid obscuring the present invention.

An embodiment of the present invention provides a method of automatedcontent source validation (CSV) for streaming data. Validation keysindicative of a content source are embedded in the data stream at aserver from where the content is served. A client requests the datastream and samples a received data stream to detect the presence ofvalidation keys to ensure that the content received is from the expectedsource. The presence of validation keys indicates the received datastream is the requested data stream, while absence of validation keysmay indicate an incorrect URL mapping may have occurred.

An Exemplary Streaming Content Delivery Network

FIG. 1 illustrates a global view of an exemplary streaming contentdelivery network (SCDN) 100 of a streaming content provider (SCP)capable of performing automated CSV of a data stream, according to oneembodiment of the present invention. As illustrated, for one embodiment,SCDN 100 comprises a server 102, clients, such as client 104 anddistribution logic 106.

Server 102 may comprise any suitable computer system and equipment togenerate and deliver streaming media content to other computer systems,such as client 104, through distribution logic 106. Distribution logic106 may comprise a public network, such as the Internet, a privatenetwork, such as a corporate network, or any combination of suitablepublic and private networks. Server 102 may acquire a media signal, andencode the media signal to create a data stream. The media signal may beacquired from a live feed of an event, as illustrated, or from aprerecorded source, such as a prerecorded song or video that may bedelivered on demand.

For one embodiment, encoding may comprise sampling the media signal andcompressing the resulting information so that it can efficiently be sentover the Internet. As an example, because many users connect to theInternet using 28.8 kilobits per second (kbps) modems, server 102 maycomprise an encoder to compress an audio signal into a 20 kbps audiodata stream. To provide users access to the data stream, server 102 maymap the data stream to a uniform resource locator (URL).

Client 104 may comprise any suitable computer system to receivestreaming media content from server 102 through distribution logic 106.For one embodiment, client 104 is a personal computer (PC) of an enduser connected to the Internet, for example, through a dial-up modem ora broadband connection. Client 104 may comprise a player program capableof playing streaming media content. Examples of the player programinclude Windows Media™ Player available from Microsoft Corporation andRealPlayer® available from RealNetworks, Inc. The player program may beintegrated into an Internet browser program as a plug-in applicationthat is loaded when the browser program detects an incoming data streamof an appropriate format. Examples of the Internet browser programinclude Internet Explorer available from Microsoft Corporation andNetscape Navigator® available from Netscape Communications Corporation.

Therefore, the end user may request to play a data stream by directingthe player program to the URL of the data stream directly, or from abrowser program. However, the end user may receive an unexpected datastream due to an incorrect URL mapping of the data stream. Oneopportunity to introduce incorrect URL mappings may arise when a list ofURLs is compiled by a reseller. For example, an Internet radio stationmay generate a song playlist by compiling a list of URLs for variousaudio streams. Incorrect mappings may also be introduced by elementsthroughout distribution logic 106 which may generate URL mappings, suchas splitters and load balancers.

A splitter is a server capable of receiving a data stream from a sourceserver and splitting the data stream to deliver copies, or split datastreams, to a plurality of clients. As an example, server 102 maydeliver a data stream to one or more splitters in an effort to providestreaming content to a larger audience of end users. Typically, a groupof splitters, such as splitter pool 110, is managed by a local loadbalancer so that the load on each splitter is managed by the local loadbalancer. A global load balancer, such as global load balancer 112, mayattempt to balance the load on a network by redirecting traffic todifferent splitter pools. As an example, while a user may request a datastream from a first server using a first URL, a global load balancer mayre-map the request to a second URL to access a copy of the data streamon one of several splitter pools managed by local load balancers.

Automated Source Content Validation

FIG. 2 illustrates a client-server view of SCDN 100 that providesfurther details of server 102 and client 104, according to oneembodiment of the present invention.

As illustrated, server 102 may comprise a processor 202 and a memory204, to store data and instructions for execution by processor 202. Forone embodiment, memory 204 may have stored therein a set of instructionsto implement a key generation module (KGM) 206, an encoder 208, and apacketizer module 210. For another embodiment, KGM 206 and/or encoder206 may comprise hardware circuitry.

Encoder 208 may encode a media signal to create a data stream of anappropriate format. KGM 206 may generate validation keys to be embeddedin a data stream created by encoder 208. Validation keys may be of anysuitable format, and may be generated according to any suitablealgorithm. For one embodiment, validation keys may comprise 32-bitnumbers.

For one embodiment, packetizer module 210 may create packets ofstreaming data by appropriately fragmenting a continuous encoded bitstream from encoder 208 such that the data packet size fits withinnetwork imposed limits. As illustrated, encoder 208 may generate encodeddata which is fed to packetizer module 210, while KGM 206 may generatevalidation keys which are fed to packetizer module 210.

As illustrated, client 104 may comprise a processor 212 and a memory214, to store data and instructions for execution by processor 212. Forone embodiment, memory 214 may have stored therein a set of instructionsto implement a key validation module (KVM) 216 and a player program 218.As previously described, a player program, such as player program 218 iscapable of playing multimedia data streams, such as audio or videostreams, or any other type of data streams.

KVM 216 may detect validation keys embedded in a data stream. For oneembodiment, KVM 216 compares validation keys detected in a data streamreceived by player program 218 to validation keys received separately.For one embodiment, KVM 216 may be a plug-in module for player program218 that enables player program 218 to play data streams with embeddedkeys.

While, as illustrated, server 102 and client 104 may comprise memory 204and memory 214, respectively, each may comprise any machine-readablemedium, including any mechanism that provides (i.e., stores and/ortransmits) information in a form readable by a machine (e.g., acomputer). For example, a machine-readable medium includes read onlymemory (ROM); random access memory (RAM); magnetic disk storage media;optical storage media; flash memory devices; electrical, optical,acoustical or other form of propagated signals (e.g., carrier waves,infrared signals, digital signals, etc.); etc.

Flow diagram 300, of FIG. 3, illustrates the operation of automatedcontent source validation (CSV) for streaming data according to oneembodiment of the present invention. For block 302, KGM 206 generatesone or more validation keys. For another embodiment, validation keys maybe generated externally and supplied to server 102 by an externalsource. Validation keys may be stored in a database at server 102.

A data stream created by encoder 208 may be mapped to a URL. For oneembodiment, KGM 206 may implement a function VK(URL, EK) that generatesvalidation keys based on the URL and an encryption key EK. Thus, aunique validation key may be generated automatically based on a URL forthe data stream. Server 102 may send the encryption key EK to client 104to enable client 104 to generate validation keys locally.

For block 304, packetizer module 210 embeds the one or more validationkeys in a data stream at the server. For another embodiment, encoder 208may embed one or more validation keys in a data stream during theprocess of encoding a media signal to create the data stream. For oneembodiment, encoder 208 may create data streams without validation keysembedded for play by player programs that are not capable of performingCSV.

Validation keys may be embedded in the data stream according to variousmethods. Validation keys may be embedded at random or predeterminedintervals. For one embodiment, packetizer 210 may add validation keysgenerated by KGM 206 to data packets such that validation keys arepresent in one of every N data packets (i.e. if N=1, every data packetwould contain validation keys). For one embodiment, N may be determinedbased on considerations such as network overhead and reliability.

FIG. 4 illustrates, for one embodiment, a data packet 400 having apacket header that specifies an offset location and length of avalidation key embedded in the data packet. As illustrated, the firstfield indicates the data packet contains a validation key, the secondfield specifies a validation key is located in the data at an offsetlocation of 1004, and the third field indicates the size of thevalidation key is 4 bytes. In other words, a player program thatreceives the data packet may parse the data packet to determine a 4-bytevalidation key is included in the data packet following 1004 bytes ofstreaming data. For one embodiment, a data packet may contain more thanone validation key.

In another embodiment, a validation key may be embedded in a data streamwrapped by predetermined data. For example, a validation key of apredetermined byte length may be preceded, and trailed by, predeterminedbyte sequences. The player program may detect the predetermined bytesequences which indicate the data in between is a validation key.Careful selection of the byte sequences can greatly reduce thelikelihood of the byte sequences occurring naturally in a data stream,which may result in an incorrect content source validation.

For block 306, client 104 requests the data stream from server 102. Therequest may result from an end user directing player program 218 to theURL of the data stream. For block 308, server 102 sends the data streamto client 104.

For block 310, client 104 obtains the one or more validation keys. Forone embodiment, the one or more validation keys are sent by server 102to client 104 through distribution logic 106, in response to a requestfor the data stream. For one embodiment, server 102 sends the one ormore validation keys to client 104 through a first connection betweenserver 102 and client 104 prior to, or while, sending the data stream toclient 104 through a second connection between server 102 and client104.

For another embodiment, client 104 obtains the one or more validationkeys prior to requesting the data stream. For example, client 104 mayreceive a formatted electronic mail (email) message containingvalidation keys, download validation keys from a website or install themas an automatic update for player program 218. Alternatively, client 104may obtain validation keys from a storage medium, such as a floppy disk,a compact disk read only memory (CD-ROM), or other storage medium knownor not yet developed.

Validation keys obtained by client 104 may be stored in a database atclient 104. FIG. 5 illustrates an exemplary database 500 to store 32-bitvalidation keys with associated URLs. For example, when player program218 requests a data stream with the URL“rtsp://www.mediaserver1/example_stream1” KVM 216 may retrieve thevalidation key E106xH (hexadecimal format) from database 500. Foranother embodiment, a URL for a data stream may be associated with morethan one validation key.

For another embodiment, client 104 may generate validation keys for arequested data stream locally as a function VK(URL, EK) of a URL of arequested data stream and an encoder key EK. For example, rather thanobtain validation keys, client 104 may obtain encoder key EK from server102 to generate validation keys as a function of the URL of a requesteddata stream.

For block 312, client 104 receives a data stream. The data streamreceived by client 104 may or may not be the data stream requested byclient 104. For example, if a URL for the requested data stream isincorrectly mapped at server 102, or at any point in distribution logic106, the received data stream may not be the same as the requested datastream.

For block 314, client 104 samples the data stream received by client 104to detect the one or more validation keys. For one embodiment, KVM 216samples the data stream received by client 104, extracts detectedvalidation keys, and outputs a data stream without embedded validationkeys for play by player program 218.

For block 316, if one or more validation keys are detected, the datastream received by the client is validated as being the requested datastream, and the YES branch is taken. A data stream received by client104 may be validated if fewer than all of the one or more validationkeys are detected. For one embodiment, if a predetermined number of theone or more validation keys are detected, the received data stream isvalidated. The predetermined number may be adjusted to accommodate poorconnections which result in lost data packets.

For block 318, client 104 communicates a valid status message to server102 and continues processing the data stream. Server 102 may, forexample, after sending a data stream from server 102 to client 104,monitor a connection between server 102 and client 104 for a validstatus message. Absence of the valid status message from client 104 mayindicate a network delivery error. For one embodiment, server 102 maygenerate an alarm message if a predetermined amount of time passeswithout receiving a valid status message from client 104 to notifyappropriate personnel of a potential network delivery error.

For one embodiment, a data stream may be validated by client 104 thefirst time one or more validation keys are detected in the data stream,and client 104 may cease to sample the data stream thereafter. Foranother embodiment, client 104 may continue to sample the data stream todetect validation keys while the data stream is received by client 104.

If one or more validation keys are not detected, for block 316, the datastream received by client 104 is invalidated as being different than therequested data stream and the NO branch is taken. For one embodiment, ifa predetermined number of validation keys are not detected, the receiveddata stream is invalidated. Absence of validation keys in the receiveddata stream may indicate an incorrect URL mapping of the requested datastream.

For block 320, an error message is generated at client 104, to indicatea CSV error has occurred. The error message may allow a user to retry,for example, to request the data stream from server 102 again, or exitwithout retrying. For one embodiment, KVM 216 may generate an errormessage if a predetermined maximum amount of streaming data is receivedwithout detecting a validation key. Similarly, KVM 216 may generate anerror message if a requested data stream is not received in apredetermined maximum time period. For one embodiment, player program218 may disable CSV in order to play data streams without validationkeys embedded.

For block 322, client 104 communicates an error message to server 102,to indicate a CSV error has occurred. When a CSV error is received byserver 102, for example, appropriate personnel may be notified of apossible network delivery error. For one embodiment, diagnosticinformation may be included with the error message, such as the URL ofthe requested data stream and any validation keys detected in thereceived data stream. Such diagnostic information may assist appropriatepersonnel in determining the source of the error, for example, where anincorrect URL mapping may have occurred.

For one embodiment, client 104 may establish a connection with server102 through distribution logic 106 that is separate from a connectionthrough which a data stream is received. Such a connection, often calledan out-of-band connection, may be used to communicate CSV statusmessages to server 102, while client 104 receives the data stream. Anout-of-band connection may provide further automation, enabling server102 to take appropriate action to correct a CSV error and monitor theout-of-band connection to determine if the error is still present.

For one embodiment, a log file may be created and updated based on CSVresults. The log file may be created at server 102 and/or client 104.For example, the log file may contain data indicative of the number ofsuccessful and unsuccessful validations that occurred for a particulardata stream, along with associated time stamps. This data could be usedto determine a measure of content delivery accuracy. Such a measure maybe useful in determining if a level of content delivery accuracyspecified in a service level agreement (SLA) between a streaming contentprovider (SCP) and a reseller has been achieved. For one embodiment, alog file generated at client 104 may be uploaded periodically by server102.

For one embodiment, specific versions of key validation modules (KVMs)may integrate with existing, readily available player programs, asplug-in modules, to enable the player programs to perform automated CSV.For example, one plug-in module may integrate with Windows Media™ Playeravailable from Microsoft Corporation, while another plug-in module mayintegrate with RealPlayer® available from RealNetworks, Inc.

For one embodiment, a system may provide an SCP with automated contentsource validation. For example, referring back to FIG. 1, an SCP mayestablish one or more clients, such as client 104, downstream ofdistribution logic 106 used to deliver streaming content from server 102to the one or more clients. The clients may be physically located toaccess streamed content through different paths in the distributionlogic, for example through different splitter pools 110. Special playerprograms at the clients may be programmed, for example, to periodicallyaccess streamed content provided by the SCP through a list of URLs.Diagnostic information received from the different clients may providethe SCP with greater assurance content is streaming properly throughdifferent paths in distribution logic 106, or may indicate elements indistribution logic 106 that may have introduced problems.

While the description above illustrated embodiments to detect incorrectURL mappings, content source validation (CSV) may be used for a varietyof purposes. For example, validation keys may be embedded in a datastream to identify content of the data stream as not intended for acertain group of users. For example, rating information (G, PG, etc.)may be provided for parental control. Player programs may be developedwith certain modes that prohibit play of data streams identified by suchvalidation keys. Validation keys for other types of restricted material,such as copyrighted material, or pay-per-view content, may bedistributed only to authorized users.

In the foregoing description, the invention has been described withreference to specific exemplary embodiments thereof. It will, however,be evident that various modifications and changes may be made theretowithout departing from the broader spirit or scope of the presentinvention as defined in the appended claims. The specification anddrawings are, accordingly, to be regarded in an illustrative rather thana restrictive sense.

1. An apparatus comprising: a database; and a server coupled with thedatabase, the server to receive a request for a data stream via aprocessor coupled with a memory, the processor to receive a uniquevalidation key associated with the data stream, the unique validationkey to map the data stream with a source, wherein the unique validationkey received is generated based on a combination of a uniform resourcelocator (URL) and an encryption key; store the unique validation key;request a data stream after receiving the unique validation key; receivethe data stream; sample the data stream to detect the unique validationkey embedded in the data stream, wherein the validation key embeddeddata stream is to ensure that the data stream includes content intendedfor an associated destination, wherein the validation key is embedded inthe data stream wrapped by predetermined data, the predetermined dataincluding a number of predetermined bytes to precede and trail thevalidation key; and validate the data stream in response to detectingthe unique validation key embedded in the data stream.
 2. The apparatusof claim 1, wherein the source comprises one or more of a source ofaudio information, a source of video information, and a source ofaudio-video information and the URL.
 3. The apparatus of claim 1,wherein the processor is further to request data to be retrieved fromthe URL.
 4. The apparatus of claim 1, wherein the processor is furtherto generate an error if the unique validation key is not detected in thedata stream.
 5. The apparatus of claim 4, wherein the processor isfurther to: create a log file; and write the error to the log file.
 6. Asystem, comprising: a server coupled with a database, the server toreceive a request for a data stream via a processor coupled with amemory, the server to receive a unique validation key associated withthe data stream, the unique validation key to map the data stream with asource, wherein the unique validation key received is generated based ona combination of a uniform resource locator (URL) and an encryption key;store the unique validation key; request a data stream after receivingthe unique validation key; receive the data stream; sample the datastream to detect the unique validation key embedded in the data stream,wherein the validation key embedded data stream is to ensure that thedata stream includes content intended for an associated destination,wherein the validation key is embedded in the data stream wrapped bypredetermined data, the predetermined data including a number ofpredetermined bytes to precede and trail the validation key; andvalidate the data stream in response to detecting the unique validationkey embedded in the data stream.
 7. The system of claim 6, wherein thesource comprises one or more of a source of audio information, a sourceof video information, and a source of audio-video information and theURL.
 8. The system of claim 6, wherein the processor is further torequest data to be retrieved from the URL.
 9. The system of claim 6,wherein the processor is further to generate an error if the uniquevalidation key is not detected in the data stream.
 10. The system ofclaim 9, wherein the processor is further to: create a log file; andwrite the error to the log file.
 11. A machine-readable storage mediumcomprising instructions which, when executed, cause a machine to:receive a unique validation key associated with a data stream, theunique validation key to map the data stream with a source, wherein theunique validation key received is generated based on a combination of auniform resource locator (URL) and an encryption key; store the uniquevalidation key; request a data stream after receiving the uniquevalidation key; receive the data stream; sample the data stream todetect the unique validation key embedded in the data stream, whereinthe validation key embedded data stream is to ensure that the datastream includes content intended for an associated destination, whereinthe validation key is embedded in the data stream wrapped bypredetermined data, the predetermined data including a number ofpredetermined bytes to precede and trail the validation key; andvalidate the data stream in response to detecting the unique validationkey embedded in the data stream.
 12. The machine-readable storage mediumof claim 11, wherein the source comprises one or more of a source ofaudio information, a source of video information, and a source ofaudio-video information and the URL.
 13. The machine-readable storagemedium of claim 11, wherein the instructions when executed, furthercause the machine to request data to be retrieved from the URL.
 14. Themachine-readable storage medium of claim 11, wherein the instructionswhen executed, further cause the machine to generate an error if theunique validation key is not detected in the data stream.
 15. Themachine-readable storage medium of claim 14, wherein the instructionswhen executed, further cause the machine to: create a log file; andwrite the error to the log file.